Although I suspect most reviewed providers have at least limited "VIP" status, I'm not certain if the limited status gives them PM access.  There's really no way of knowing whether anyone, provider or hobbyist, has PM access.  I suggest regular email unless you are specifically informed by the provider that a PM thru TER is acceptable.

If she is a VIP member, there will be a box at the top that says "send private mail to provider."  Click on that box, and then a window will open where you can write and send a mail to her.

Thanks everybone, I figured out how to do it, if a provider has two names make it into one long name then it will send it.